Development and Implementation of an Online Estimator for Oxygen Transfer in Bioreactors Using Recursive Least Squares

Currently, there is not a standard means to calculate or measure the oxygen consumption of a cell culture online in a bioreactor. The oxygen transfer rate is directly related to the oxygen uptake rate of the cells. This quantity can be estimated by comparing the input and offgas oxygen concentrations, however, this estimation does not contain high-frequency information about the oxygen transfer rate. An online estimator has been developed that uses measurements of the oxygen concentration in the input gas, in the fluid of the bioreactor, and in the offgas exiting the bioreactor to predict the oxygen transfer rate to the fluid of a bioreactor. Recursive least squares is implemented to fit a model for the mass transfer coefficient, and from this, the oxygen transfer rate can be calculated. Learn More